Wastewater Collection

The wastewater collection system in Corvallis gathers sanitary sewage from sinks, tubs, toilets, and other household and commercial drains, and transfers it to the wastewater plant for treatment. There are over 200 miles of pipe ranging in size from 4 to 72 inches in diameter that make up the collection system, along with 3,900 manholes which provide access to the system. 

In the older sections of Corvallis (about 30% of the entire collection system), the sanitary and storm systems are combined and go to the wastewater plant for treatment. The rest of the City's system and all new development are two separate piping systems. The Combined Sewer Overflow Remediation was undertaken to mitigate the situation where the collection system reaches capacity from excess storm water during heavy rainfall events, causing diluted untreated sanitary sewage to overflow to the Willamette River. This construction project was substantially completed and placed in operation in 2001. 

Corvallis Public Works Department inspects the wastewater collection system using state-of-the-art technology including remote video camera inspections and smoke testing of sanitary lines. If you experience a sewer back-up, call Public Works at 541-766-6916 to report the problem. We'll dispatch a truck to investigate and clean out the main sewer line if needed. If the problem is in the service line between the sewer main and your house, you should contact a plumber to diagnose the problem or a private sewer cleaning service to have the line cleared. 

For more information or to report problems with the wastewater system, call Public Works at 541-766-6916.